Length of wier for overflow - with Wavebox

[AcroSteve]

I am planning a 6' tank which most likely, will have an external overflow.

Location wise, I would prefer to have the overflow on one of the ends, rather than the back of the tank. However, I am willing to go to great lengths to minimize noise and optimize performance..

So, with the wavebox, I think that requires a center overflow. My thoughts where with the 6' length, 2' of overflow in the center would work pretty well. I would like to make the wier as wide as possible, so how much "regular tank" should I leave on each end?

Thanks

 

[InsaneClownFish]

I'm tagging along for this too. I'm having an 8ft tank built and want to keep the overflow on the short right hand wall- the same wall I want the wavebox. After thinking about this, and reading your post Steve, I figured the center overflow would be best.

I'd like to hear more about this. Can an overflow be on the same far side, or the opposite side, of an overflow?

 

[rvitko]

Center overflows are ideal because the water level doesn't change much in the center, you don't lose wave energy to an overflow this way and you don't have the splash. If the overflow is centered I would position it where you want the static water line, so if you figure on a 1.5" wave it should be about 2" from the top so you have a half inch safety margin. The overflow size would be an issue of the amount of return flow you plan on from the sump and not dependent on the wavebox.

 

[AcroSteve]

OK.

You said what I was thinking when you mentioned the energy loss.

I suppose for maximum surface skimming, the wier length would be the length of the tank. However, that would result in loss of energy on the ends of the tank.

I guess what I want to know is, to retain as much of that energy as possible, how far in from each end should the wier begin? Is 6" enough? I suppose not, but I also feel that 24" is excessive.

Can you guesstimate a recommend minimum?

 

[rvitko]

I think 24" would be fine but likely 12-18" is good enough. The main factor to consider is the flow through the overflow and I would discuss that with the tank manufacturer to get the proper sizing.

 

[AcroSteve]

Well, that would result in me talking to myself.

Not sure which one of us knows more. :lol:

 

[rvitko]

I think if the design is comparable to what the big manufacturers use like Oceanic you should be in good shape.